A read head includes a permanent magnet (PM) layer formed up to 100 nm behind a free layer where PM layer magnetization may be initialized in a direction that adjusts free layer (FL) bias point, and shifts sensor asymmetry (Asym) closer to 0% for individual heads at slider or Head Gimbal Assembly level to provide a significant improvement in device yield. Asym is adjusted using different initialization schemes and initialization directions. With individual heads, initialization direction is selected based on a prior measurement of asymmetry. The PM layer is CoPt or CoCrPt and has coercivity from 500 Oersted to 1000 Oersted. The PM layer may have a width equal to the FL, or a width equal to the cross-track distance between outer sides of the longitudinal bias layers. In another embodiment, the PM layer adjoins a backside of the top shield.

A data storage device is disclosed comprising a head actuated over a magnetic media comprising a plurality of tracks. A first pattern of magnetic transitions is written to a first segment of a first track. Preparation is made to write a second pattern of magnetic transitions to a second segment of a second track adjacent the first segment of the first track. When the second pattern matches the first pattern, a write boost is configured to a first setting, and when the second pattern does not match the first pattern, the write boost is configured to a second setting. The second pattern of magnetic transitions is then written to the second segment of the second track using the configured write boost.

According to one embodiment, a magnetic recording device includes a magnetic head, and an electrical circuit. The magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body provided between the first and the second magnetic poles. The stacked body includes a first nonmagnetic layer, a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole, a first layer provided between the first magnetic layer and the second magnetic pole, a second nonmagnetic layer provided between the first layer and the second magnetic pole, a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole, and a third nonmagnetic layer provided between the second magnetic layer and the second magnetic pole. The electrical circuit supplies, to the stacked body, a first current having a first orientation from the second magnetic pole toward the first magnetic pole.

An apparatus comprises a write pole for writing data to a magnetic recording medium and a near-field transducer (NFT) optically coupled to a laser source and configured to produce a thermal spot on the medium. A laser driver applies laser operation power (Iop) to the laser source. A channel circuit generates symbols having a length of nT, where T is a channel clock rate and n is an integer. The laser driver applies Iop to the laser source and a write driver applies bi-directional write currents to the write pole to record the symbols at a location of the thermal spot on the medium, wherein a duration of applying Iop to the laser source by the laser driver is dependent on a length of the symbols and the effective thermal spot size.

The present disclosure generally relates to a magnetic media drive employing a magnetic recording head. The magnetic recording head comprises a main pole, an EAMR stack disposed on the main pole, and a trailing shield disposed on the EAMR stack. The EAMR stack comprises a seed layer disposed on the main pole, a spin torque layer disposed on the seed layer, and a spacer layer disposed on the spin torque layer. At least one surface of the spacer layer in contact with the spin torque layer has a smaller or reduced area than the spin torque layer. The at least one surface of the spacer layer in contact with the spin torque layer is recessed from a media facing surface and has a smaller cross-track width than the spin torque layer and a smaller width in the stripe height direction than the spin torque layer.

Systems and methods are disclosed for dynamically adjusting parameters used during a read operation to reduce stress on a read head. In certain embodiments, an apparatus may comprise a read head configured to read data stored to a data storage medium, and a control circuit that controls a parameter of the read head influencing the read head's ability to accurately read data. The control circuit may be configured to extend the working lifespan of the read head by monitoring a read performance of the read head, and adjusting the parameter to reduce the read performance when the read performance is greater than a first threshold.

A spin-orbit torque (SOT) magnetic tunnel junction (MTJ) device includes a substrate, a seed layer over the substrate, and a bismuth antimony (BiSb) layer having (0120) orientation on the seed layer. The seed layer includes a silicide layer and a surface control layer. The silicide layer includes a material of NiSi, NiFeSi, NiFeTaSi, NiCuSi, CoSi, CoFeSi, CoFeTaSi, CoCuSi, or combinations thereof. The surface control layer includes a material of NiFe, NiFeTa, NiTa, NiW, NiFeW, NiCu, NiCuM, NiFeCu, CoTa, CoFeTa, NiCoTa, Co, CoM, CoNiM, CoNi, NiSi, CoSi, NiCoSi, Cu, CuAgM, CuM, or combinations thereof, in which M is Fe, Cu, Co, Ta, Ag, Ni, Mn, Cr, V, Ti, or Si.

A perpendicular magnetic recording (PMR) writer is disclosed wherein an insulation layer is formed between a top yoke (TY) and an uppermost (PP3) trailing shield to electrically isolate the main pole (MP) from a trailing loop for magnetic flux return. One or both of a first non-magnetic (NM) metal layer and a second NM metal layer are formed between the MP tip and a hot seed layer and side shields, respectively, to form an electrical path that is in parallel to that of a dynamic fly height (DFH) heater circuit. MP tip protrusion is enhanced and writability is improved especially for track widths <40 nm, and is tunable by the volume of the first and second NM layer, and the composition of the NM metals. Existing writer pad layouts may be employed and there is no additional cost to PMR backend processes.

Aspects of the present disclosure provide various magnetic recording slider structures and fabrication methods that can reduce head overcoat (HOC) thickness without significantly reducing the lifetime and reliability of a slider by using a protective cap placed on preselected locations on the outermost surface or HOC of the slider. A slider includes a writer comprising an energy-assisted recording element. The writer is configured to store information on a magnetic medium using the energy-assisted recording element. The slider includes a head overcoat (HOC) layer providing an outermost media facing surface. The slider further includes a protective cap positioned on the HOC layer to at least partially cover the energy-assisted recording element, the protective cap including a preselected shape configured to protect the energy-assisted recording element.

The present disclosure generally relates to spin-orbital torque (SOT) differential reader designs. The SOT differential reader is a multi-terminal device that comprises a first shield, a first spin hall effect layer, a first free layer, a gap layer, a second spin hall effect layer, a second free layer, and a second shield. The gap layer is disposed between the first spin hall effect layer and the second spin hall effect layer. Electrical lead connections are located about the first spin hall effect layer, the second spin hall effect layer, the gap layer, the first shield, and/or the second shield. The electrical lead connections facilitate the flow of current and/or voltage from a negative lead to a positive lead. The positioning of the electrical lead connections and the positioning of the SOT differential layers improves reader resolution without decreasing the shield-to-shield spacing (i.e., read-gap).